title: Incidence and pathology of repeat computed tomography of the abdomen and pelvis in a pediatric emergency department population.
abstract: OBJECTIVE
  Computed tomographic (CT) scanning is increasingly prevalent in emergency departments (EDs). It is a moderate- to high-radiation diagnostic technique that exposes more than 1 million children per year to unnecessary radiation. Repeat CT of the abdomen and pelvis (CTAP) among pediatric patients who return to the ED within 1 year may be an example of unnecessary pediatric radiation exposure. The objectives of this study were to identify the incidence of pediatric patients who undergo more than 1 CTAP within 1 year and to detect the incidence of significant pathology on these repeat scans.
  
  
  METHODS
  This was a retrospective review of subjects younger than 18 years with an initial CTAP as an ED patient, inpatient, or outpatient and a second CTAP within 12 months and during an ED visit.
  
  
  RESULTS
  During the observation period, 172 pediatric ED admissions had at least 1 repeat admission involving an abdominal CT scan. Thirty-seven of the CT scans (19.3%) were positive. Sixty percent of the positive cases (n = 22) were attributable to the 3 most prevalent diagnoses: appendicitis in 8 cases (21.6%), kidney stone in 8 cases (21.6%), and colitis in 6 cases (16.2%). Approximately, one third of repeat CT scans occurred within the first month of the initial CT scan, and two thirds occurred within 6 months of the initial CT scan.
  
  
  CONCLUSIONS
  A substantial percentage of pediatric patients undergo more than 1 CTAP within a 1-year time frame. Among these patients, a large portion were diagnosed significant pathology.
authors.affiliation: Department of Emergency Medicine, Staten Island University Hospital, Staten Island, NY 10305, USA. barryjhahn@gmail.com
authors.forename: Barry
authors.initials: B
authors.lastname: Hahn
authors.forename: Jennifer
authors.initials: J
authors.lastname: Dima
authors.forename: David
authors.initials: D
authors.lastname: Hirschorn
authors.forename: Kera F
authors.initials: KF
authors.lastname: Weiserbs
mesh_terms: D000293:Adolescent; D002648:Child; D002662:Child Health Services / Q000706:statistics & numerical data*; D002675:Child, Preschool; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D005767:Gastrointestinal Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology; D005831:Genital Diseases, Female / Q000000981:diagnostic imaging / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007223:Infant; D007297:Inpatients / Q000706:statistics & numerical data; D008297:Male; D053040:Nephrolithiasis / Q000000981:diagnostic imaging / Q000453:epidemiology; D010045:Outpatients / Q000706:statistics & numerical data; D010359:Patient Readmission / Q000706:statistics & numerical data; D010388:Pelvis / Q000000981:diagnostic imaging*; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control; D011860:Radiography, Abdominal / Q000009:adverse effects / Q000706:statistics & numerical data*; D012008:Recurrence; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000009:adverse effects / Q000706:statistics & numerical data*; D019564:Unnecessary Procedures